吊拖船队通过限制性顺直航段安全限制因素研究

为了保障吊拖船队通过顺直航道的航行安全,充分考虑吊拖船队的柔性结构特征和航道条件,深入研究限制性航道顺直航段航道特点,运用船舶操纵与引航理论,建立以吊拖船队为研究对象的顺直航段航道宽度计算模型,从而确定针对航道宽度的吊拖船队通过顺直航段的安全限制因素,运用实船试验数据和现有航道维护尺度对建立的公式进行验算。提出了符合我国运河航道条件和吊拖船队航行特点的运河限制性航道顺直航段航道宽度计算公式,以期为保障吊拖船队在顺直航道安全航行提供理论支撑,弥补我国运河以吊拖船队为主要船型的航道技术尺度计算方面的不足。     

Evaluation of geometrically personalized THUMS pedestrian model response against sedan–pedestrian PMHS impact test data

Objective: Evaluating the biofidelity of pedestrian finite element models (PFEM) using postmortem human subjects (PMHS) is a challenge because differences in anthropometry between PMHS and PFEM could limit a model's capability to accurately capture cadaveric responses. Geometrical personalization via morphing can modify the PFEM geometry to match the specific PMHS anthropometry, which could alleviate this issue. In this study, the Total Human Model for Safety (THUMS) PFEM (Ver 4.01) was compared to the cadaveric response in vehicle–pedestrian impacts using geometrically personalized models.

Methods: The AM50 THUMS PFEM was used as the baseline model, and 2 morphed PFEM were created to the anthropometric specifications of 2 obese PMHS used in a previous pedestrian impact study with a mid-size sedan. The same measurements as those obtained during the PMHS tests were calculated from the simulations (kinematics, accelerations, strains), and biofidelity metrics based on signals correlation (correlation and analysis, CORA) were established to compare the response of the models to the experiments. Injury outcomes were predicted deterministically (through strain-based threshold) and probabilistically (with injury risk functions) and compared with the injuries reported in the necropsy.

Results: The baseline model could not accurately capture all aspects of the PMHS kinematics, strain, and injury risks, whereas the morphed models reproduced biofidelic response in terms of trajectory (CORA score = 0.927 ± 0.092), velocities (0.975 ± 0.027), accelerations (0.862 ± 0.072), and strains (0.707 ± 0.143). The personalized THUMS models also generally predicted injuries consistent with those identified during posttest autopsy.

Conclusions: The study highlights the need to control for pedestrian anthropometry when validating pedestrian human body models against PMHS data. The information provided in the current study could be useful for improving model biofidelity for vehicle–pedestrian impact scenarios.     

计算毒理学在内分泌干扰物筛选上的应用和展望

内分泌干扰物通过干扰内分泌系统导致多种疾病,如生殖疾病、肥胖症甚至癌症。然而,面对环境中大量潜在的内分泌干扰物,传统的体外、体内评估方法由于成本高、耗时长等问题,难以实现内分泌干扰物的高通量筛查。计算毒理学逐渐发展成为被美国环保局(Environmental Protection Agency,EPA)、经济合作与发展组织(Organization for Economic Co-operation and Development,OECD)等机构所推荐的内分泌干扰物筛选与预测方法。本文综述了计算毒理学在内分泌干扰物筛选上的进展,主要包括分子对接和分子动力学模拟的应用,并对有害结局路径(adverse outcome pathway,AOP)的方法进行介绍和展望。     

Assessment of leaching behavior and human bioaccessibility of rare earth elements in typical hospital waste incineration ash in China

Leaching behavior and gastrointestinal bioaccessibility of rare earth elements (REEs) from hospital waste incineration (HWI) fly and bottom ash samples collected from Beijing and Nanjing Cities were assessed. In the same ash sample, the leaching concentrations of individual REEs determined by the Toxicity Characteristic Leaching Procedure (TCLP) were higher than those detected by the European standard protocol (EN-type test), thereby suggesting that the low pH value of leaching solution was an important factor influencing the leachability of REE. The REE bioaccessibility results, which were evaluated using the physiologically based extraction test (PBET), indicated that REEs were highly absorbed during gastric phase by dissolution; and subsequently precipitated and/or re-adsorbed in small intestinal phase. The relative amounts of the total REEs extracted by the TCLP method, EN-type test and PBET test were compared. In addition to the pH value of extraction solutions, the chelating role of REEs with organic ligands used in the PBET method was also an important parameter affecting REE adsorption in human body. Additionally, this study showed that REEs were extracted by these methods as concomitants of heavy metals and anions (NO₃ ^–, F^–, SO₄ ^2–, and Cl^–) from HWI ash, which probably caused the remarkably complex toxicity on human body by the exposure pathway.

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Copper recovery from waste printed circuit boards concentrated metal scraps by electrolysis

Copper recovery is the core of waste printed circuit boards (WPCBs) treatment. In this study, we proposed a feasible and efficient way to recover copper from WPCBs concentrated metal scraps by direct electrolysis and factors that affect copper recovery rate and purity, mainly CuSO₄·5H₂O concentration, NaCl concentration, H₂SO₄ concentration and current density, were discussed in detail. The results indicated that copper recovery rate increased first with the increase of CuSO₄·5H₂O, NaCl, H₂SO₄ and current density and then decreased with further increasing these conditions. NaCl, H₂SO₄ and current density also showed a similar impact on copper purity, which also increased first and then decreased. Copper purity increased with the increase of CuSO₄·5H₂O. When the concentration of CuSO₄·5H₂O, NaCl and H₂SO₄ was respectively 90, 40 and 118 g/L and current density was 80 mA/cm², copper recovery rate and purity was up to 97.32% and 99.86%, respectively. Thus, electrolysis proposes a feasible and prospective approach for waste printed circuit boards recycle, even for e-waste, though more researches are needed for industrial application.

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The use of ultrasound-assisted anaerobic compost tea washing to remove poly-chlorinated dibenzo-p-dioxins (PCDDs), dibenzo-furans (PCDFs) from highly contaminated field soils

The remediation of dioxin-contaminated soil of a specific coastal area previously employed for the manufacture of pentachlorophenol (PCP) in southern Taiwan’s Tainan City has attracted much attention of researchers there. This work addresses the possibility of providing an effective and environmentally friendly option for removing PCDD/Fs from soil in that field. Soil screening/sieving was first conducted to assess particle distribution. Fine sand was observed to be the major component of the soil, accounting for more than 60% of the total mass. A combination of ultrasonification and mechanical double-blade agitation was used to facilitate the washing of the soil using the biosurfactant anaerobic compost tea. More than 85 and 95% of total removal efficiencies were achieved for moderately and highly contaminated soils after 6 and 10 washing cycles, respectively, under ambient temperature, a soil/liquid ratio 1:2.5, 700 rpm, and over a relatively short duration. These results were achieved through the collision and penetration effects of this combined treatment as well as PCDD/F partitioning between the particles and anaerobic compost tea. This study represents the first to report the use of anaerobic compost tea solvent to wash soil highly contaminated by dioxin. It was concluded that anaerobic compost tea, rich in non-toxic bio-surfactants (e.g., alcohols, humic acids), can be used to improve bioavailability and bioactivity of the soil making bio-attenuation and full remediation more efficient.     

De novo formation of dioxins from milled model fly ash

Environmental Science and Pollution Research - Municipal solid waste incineration (MSWI) fly ash has been classified as hazardous waste and needs treatment in an environmentally safe manner....     

Impacts of climate change in rapidly urbanizing region-a case study in Hangzhou(China)

Climate change is expected to be a major driving force of landscape in the coming decades.It will have a multitude of potential impacts that vary in intensity and effect according to region and sector.In the context of global warming,the climate of China has changed significantly in the recent 100 years.The reason for climate change in China is mainly due to irrational land use caused by human activities,which chiefly results in the rapid industrialization and urbanization process.Based on an assessment model,this research represents a picture of the impacts of climate change in six districts of Hangzhou region.The aim of this paper is to conclude,on the one hand,some of Hangzhou sensitivities in relation to the primary effects of climate change.On the other hand,a reflection is made on a methodology to formulate preconditions on a scientific basis for further research by design of integrated adaptation options for the future spatial developments in function to upgrade Hangzhou resilience in relation to climate change challenges.     

Generation of solid wastes in typhoon disasters and their emergent cleaning and treatment means

In Taiwan, typhoons usually result in a large amount of waste that needs to be removed in a short time from July to October. This study reviewed the relevant regulations on the clean-up of typhoon waste, including emergency response regulations, organizations and information systems; and we also discuss different typhoon waste clean-up and disposal methods. The results indicate that the parameters other than the maximum wind speed, such as the maximum accumulated rainfall, flooded area, waste output, sludge output, disinfected area and government dispatched attendance reached statistical significance (p < 0.05). Waste, tree branches and bird carcasses were primarily incinerated, while silt and building materials were buried, and pig and cattle carcasses were placed in a landfill with the tertiary treatment of wastewater. This study also reports on the relevant regulations for prevention of epidemics among personnel working in disaster areas. The results can provide important references for the disposal of typhoon waste in developing countries. As Asian countries have similar life styles and are often attacked by typhoons, the results of this study provide Asian countries with the operating experience of Taiwan in emergency treatment of solid waste resulting from typhoons as a reference for them to plan response systems and operation.     

Potential toxicity of amphenicol antibiotic: binding of chloramphenicol to human serum albumin

Antibiotics are widely used in daily life but their abuse has posed a potential threat to human health. To evaluate the toxicity of chloramphenicol (CAP) at the protein level, the interaction between CAP and human serum albumin (HSA) was investigated by fluorescence, Ultraviolet–visible (UV–Vis) absorption, Fourier transform infrared (FT-IR) spectroscopy and molecular docking methods. Fluorescence data revealed that the fluorescence quenching of HSA by CAP was the result of the formation of CAP–HSA complex, and the binding constant was determined to be 3.196?×?10⁴ L mol^?1 at 310 K. The thermodynamic determination indicated that the interaction was driven by enthalpy change and entropy change together, where the multiple hydrogen bonds (CAP and the residues Arg 222 and His 242 of HSA) and van der Waals forces were the dominant binding force. The site marker competition revealed that CAP bound into sub-domain IIA of HSA. The binding of CAP induced the drastic reduction in α-helix conformation and the significant enhancement in β-sheet conformation of HSA. Molecular docking study further confirmed the binding mode obtained by experimental study. This work provides a new quantitative evaluation method for antibiotics to cause the protein damage.